Highway crossing signal system



1934- w. s. HENRY ET AL 1,969,075

HIGHWAY CROSSING SIGNAL SYSTEM Filed Jan. 20, 1931 2 Sheets-Sheet 1 FIG. 1.

INVENTOR51 W5. Henry 4 SJ? Mac key ATTORNEY Aug. 1934- w. s, HENRY ET AL 1,969,075

HIGHWAY CROSSING SIGNAL SYSTEM Filed Jan. 20, 1931 2 Sheets-Sheet 2 INVENTORS M ATTORNEY Patented Aug. 7, 1934 HIGHWAY CROSSING SIGNAL SYSTEM William S. Henry, Goldwater, and 7 Stuart J.

Mackey, Rochester, N. 1., assignors to General Railway Signal Company, R ochester, N. Y."

Application January 20,

15 Claims. (01.- 246-130)] This invention relates in general to signalling systems, and has more particular reference to a highway crossing signal system of an improved form. 1

In highway crossing signals employing usual interlocking relays, if a train enters one of the usual detector track sections, at one side of a highway at a. time when the other detector track section at the other side of the highway is shunted, or de-energized. or open circuited,

from any cause whatsoever, the interlocking relay for the side ,of the entering train is already latched up, and hence they train cannot warn of the danger due to its approach to the highway by energizing the highway crossing signal. In other words, there is no protection afforded by the highway signal against a train approaching the highway under such conditions. The short-circuiting or shunting referred to, of one of the detector track sections, can occur due to a maintainer testing the track circuit, to a sleigh runner or the like over the track rails, or

to other means. I

One of the objects of the present invention is to protect against aflcombination of circumstances as pointed ,out above, whereby to prevent a train from approaching the, highway without manifesting its presence by energizing the crossing signal. I

Further objects, purposes and characteristic features will appear as the description .progresses, reference being made to the accompanying drawings, showing, solely by way of example,-

and in no manner in a limiting sense, two formswhich the invention can i assume. -In the draWings:- I Fig. 1 is a diagrammatic view showing on form of the invention.

Fig. 2 is a fragmentary diagrammatic view, showing structural features of a part of the invention.

Fig. 3 is a diagrammatic view showing a second form of the invention.

Fig. 4 is a diagrammatic view showing a further modification of the invention.

Referring to the drawings, and first to Fig. 1,

there is here shown a stretch of single track constituted by track rails 1, separated into insulated blocks A, B and C by insulating joints 2, each of the blocks being supplied with-track circuit current as from a battery 3, through a limiting resistance 3, and having connected across its other end a track relay, TR TR, TR

respectively.

Crossing the rack is a highway HW, and for:

1931, .Serial No. 569,976.

indicating the 'approach'of a train to the high--' way, there is provided a flashing light FL, of any usual or desired form, such for example, as that shown in the patent of S. M. Day, No.- 1,902,799,granted March 21, 1933. Controlled through a front point of the track relay connected to the block B, across, and wholly within, whichthe highway passes, is an interlocking latching relay IR. This relay IR, as shown in Fig. 2, includes two pivoted arma tures, 4 and5, biased-by gravity to move downwardlylagainst stops Sand 7, and held in the full line position, .shown in'Fig. 2, when armature 8 is energized. v Asfshown in: Fig. 2, contact carrying armatures 9 and 10 of relays TR". and TR respectively, are so positioned with respect" to the pivoted armatures 4 and5 as to belocked against moving'to full released position .by the armatures 4 and .5,"1if such; armatures are down, and were released prior to the release of 'armatures 9 and 10 respectively. When .de-energized in such circumst'ances, the armatures of relays .TR" and TR move-toward full released position, but are prevented .from moving far enough to "close their back conta'ctsi 1 w Referring again'to' Fig. 1 .theoperation of the system is as follows:--'Assuming a .west bound train-entering block A, relay'TR releases its contact finger 10 to'thereby energize the flashing light FL, through acircuit including one terminal (-1-) of a source of-energy, contact finger 10- and back point-of relay TR wires 11, 12 and 13, signal FL, and. the other terminal of the source of energy, whereby to cause-a flashing signal to be displayed, and'wa'rntraffic on the highway ofapproaching danger. As the "train continues toward the highway, and occupies: block B, I relay TR releases its armature to thereby de-energize interlocking relay IR, which is normally energized through a circuit including contact finger 14 and front point of TR. and wire 15. Thispermits the latching pivoted armature's 4 and 5, to move underthe force of gravity, against their stops 6' and 7. 1 The armature 5 takes a position above armature 10, since armature 10 is already in released position, and hence armature 10 cannot be locked in-its released position. The armature 4, however, takes a position beneath armature '9-- of relay "PR", to thereby lock armature 9 against'moving'to its full released position. -Upon' block A becomingunoccupied, relay TR picks up, to thereby break the energizing circuit for the flashing light. FL, traced'above. An

PATENT orifice Furthermore, if the relays 'IR and*TR -'be not wound and proportioned so as to allow them,- on being energized, to pick up their-contact; fingers in spite of IR being,de'+en ergiz edandhaving its contact fingers, 4 and 5. down, it is obvious that the above described desirableresults" still obtain. Thus, the relays can be; a justed so that with relay IR down, it either does, or does notlock :the contact fingers of TR and TR down. Upon the train occupying block 0, relay TR is de-energized, but its contact finger 9'cannot move to full released position; since it is latched up by armature 410i interlocking relay IR. On block B becoming unoccupied, relay r TR picks up, to thereby de-energ'ize S the flashing light FL, andre-energize the interlockingrelay IR. The interlock between thea-rmature4 and armature 9 continues, however, as. thewrelays are so adjusted thatthe armature:-9,= locksz4 down,'until blockC becomes unoccupied, where upon relay IR is re-energized, .andraisesv its armature 9 sowasf-to release the armaturez4 and permit all parts. tolberestored to the normal positions'as shownin Figil; 1 1 Inthis manner a train. approachingthe high= way. crossing causesta flashing light-' in'good time to warn highway traffic. ofp-the approaching danger, and does not latch up the relay for: the approach block. on the" opposite side. of.

the highway, until thetrain is;practically.;at

the crossing. Shouldan -approaching west bound. train deeenergize the relay-IR, after hav: ing de-energized relay TR the relay: 'I'R9'would be locked 31117,; and if, "at this time, an east bound train-should occupy-the block: C, the relay: 'I'R9- would be de-jenergized-andzwould relea'seits armature'9; ..to--lock the armature 8 in retracted position, so that,.if athe west bound train were to back out of the 'blo'cksB :and'A, the east bound train could notmanifesti its;

presence by: energizing the signal FL; Thus, a train entering block A; for ,example, =;to"load, or

unload, and; then backing out of the block-A, cannot prevent a warning signal .being given by astrai'n j approaching the highway, vfrom ,-the opposite direction, and entering block C; i

:Eurthennore, should 350118: of the, blocks -Av or C become shunted (sayqmomentarily), as; by a sleigh runner, or a crow bar, 'orthe like, or due to a test .being made .of the. trackcircuit, this cannot lock up thesystem so as to prevent a train, approaching the highway-and occupying theyother of these two blocks at this time; from manifesting its presence both at once, and-after; thesfirst said shunt shall-havebeen removed, "by energizing the crossing; gsignal;

Theoperation of the interlockingorlatching;

I relay IR,: andoithe track relays TR and, TR isdiagrammatically; shown in Fig;- 2, from-which: it can :be" seen .that :the; interlocking relayv can lock either or ,both ofthe other two-.urelays I ag'ainstm'ovihg; to} full released position,-i. e.,

against closing their back contacts, if the interlocking relay is first de-energized. Furthermore, each of the relays TR and TR is designed so it can lock the respective cooperating armature of the interlocking relay, in released position, if such relay TR or IR? is de-energized after relay IR. has been de-energized andhas released its armatures. Also the relays are preferably, although not necessarily (see above) so designed that relays TR and TR when enerigized, are able to move their armatures 9 and to attracted position, even though the armatures '4 and 5 of the lock relay IR, be retracted at the; time," after which, if relay IR still be Jde-energized, its armatures 4 and 5 will move to retracted position. vIn Fig. 3 is shown a slightly modified form of the invention,in' which the interlocking relay IR'of Flg.' '1, has been replaced by two separate interlocking relays IR and IE The operation is exactly the same as described above, the change merely substituting, for the relay IR of Fig. 1, which is in eiTect a double relay having two separate armatures 4 and 5, two separate relays having the armatures 4 and "5 respectively. By using separate relays, the advantage is obtained of being able to position each inter locking relay adjacent its track relay with which it cooperatesandlocks, and undercer tain conditions it maybe desirable foreconomy in wiring and thelike, to use the arrangement of Fig. 3 in placeiof that of Fig. 1. X Referring now to Fig. 4, another form of the invention is shown, wherein thettrack is divided; in the same manner as above described," into insulated blocks' A, B and C with a highway, I-IW, crossing-the track,, and included, in block B. In this'form ofthe invention, the interlock ing or latching relay IR has the'armatures 4 and 5, for respectively locking-the armatures 9 and 10 of track 'relays 'I'R and TR of the respective blocks 61' and A, inthe same manner as described above, and illustrated in Fig. 2. 1 The interlocking relay IR, howevenis controlled'infa' different manner. It has one energizing circuit, as in Fig; 1, including contact finger-.14 and front point of relay TR,'and wire and 15 .The relay IR'als'oi'has "a second energizing circuit, including contact finger .16 and front point of relay-TR wire' 17, contact finger 18 and frontl'point'ofrelay'TR, and wires 19 and 15 From a consideration of these ener-' gizing circuits forthe interlocking relay IE, it'- Will be seen that de-energization of the inter-;

locking relay requiresnot only that the block B be shunted to thereby de-energize relay TR, but in addition that," simultaneously therewith,

one of the blocks A and C alsoi be shunted, to

not itself manifest its presence when'occupying the'other approach track section regardless of whether or not the first mentioned-approach track section meantime should becomefunoca cupied;

As a further safeguard against dangerous conditions, the arrangement of Fig. 4 cares for a short-circuited or shunted condition of 'the short track section B. Should a sleigh, or the '5 like, interconnect the rails of section B, this would cause relay TR; to release, but would not in itself de-energize the interlocking relay IR, since its second energizing circuit, passing through the front points in series of the relays TR," and TR would be intact. Thus, an approaching train, on entering block -A for example, while a sleigh or the like is interconnecting the rails of the block B, de-energizes relay IE to thereby close'an additional energizing circuit for the flashing light FL, through a circuit including contact finger 10 and back point of TR and wires 11, 12 and 13, to thereby warn of the approaching danger and continue to warn of this danger after the sleigh shunt in block B has been removed. Had the lock relay IR been de-energized by the shunt across block B, the approaching train on block A could not have closed the circuit through 10, 11, etc., for energizing the signal FL; so that, upon the shunt across B being removed, no warning signal would remain in operation to manifest th presence of the train in block A.

In this form of the invention, the interlocking'relay IR should be slow enough on release, to allow the track relay of the approach section to release ahead of it, and if it is not inherently slower in action, it can be made so by any suitable means, such as a short-circuited copper band or the like, asindicated in Fig. 4.

In the system shown in Fig. 4, there isthus provided means for preventing signal failure when an approaching train enters an approach detector track circuit, at the time there is a shunt, across either the other approach track circuit, or across the short track circuit B ineluding the highway. In the case where the system is employed in a cold climate, where sleighs are generally used, with a series of sleighs passing over the highway, and perhaps continuously shunting the track rails 'of the short track section, itcan be seen that the arrangement of Fig. 4 has distinct advantages.

' The above described forms ofinvention there' fore provide against a very usual defect in usual systems of this character, wherein the interlock provided, is effective as soon as an appreaching train manifests its presence by causing a highway signal to function, and thereby locks the system up to prevent a train approaching from the other direction from manifesting its presence.

The above described systems are of particular advantage in cases where trains approach a crossing for loading or unloading, and then back away from the crossing, the usual crossing signal system in such'cases being practically useless, since all the time that the train is on one of the approach track sections, there is no safeguard against a train approaching from the other direction.

In any of the forms above described, it is to be understood that the various relays employed, can, if desired, be indirectly controlled by the W track circuits, as by repeating a track relay,

and need not be directly connected to the track circuits, as shown solely for the sake of illustration, in this application.

Ihe above specific description of several forms of inventions, has been given solely by way of illustration, and is not intended, in anyv man-: ner whatsoever, in a limiting sense. Obviously, this invention can assume many different .physical forms, and is susceptible'of numerous modifications, and all such forms and modifications, are intendedto be included by this invention, as come within the scope of the appended claims;

Having described our invention, .we now claimz- 1. In a highway crossing signal systemifor w railwaysya stretch of single'track, a highway crossing the track, a signal, means for automatically energizing the signal upon'the approach of a train'to the highway. from either direction, and means effective upon a closer approach. of the trainto the highway for preventing the approach of. a train from the other direction from controlling the signal. a Y

.2. In 'a highway crossing signal system .for railways, a stretch of. single track, a highway crossing the track, a signaLtwo-initiating means each for automatically. energizing the. signal upon; the approachof a trainto the highway from either direction, and means eife'ctive only upon a closer approach of the train to the highway for preventing efiective operation of an initiating means for thus preventing theap-l proach of a train from the otherdirection from controlling the signal.

3. In a railway highway crossing signal system, in combination, with a highway crossing a stretch of single track, and a signal,.an .iso-1 lated track section at each side'of the crossing, and an isolated track section including the highway, signal initiating means-for eachside.sec.-. tion normally responsive to occupancyof its section to energize the signal, and lock' means responsive to occupancy of the highway section to. prevent the said normal responseof anysaid initiating means that has not already responded from energizing the signal.

4. In a railway highway crossing signal.'systerm, in combination with a highway crossing a stretch of single track, and'a' signal, an isoilated track section at each side of the crossing, and an isolated track section including the-highway, signal initiating means for-each side-section normally responsive to occupancy of' its' section to energize the signal, andlock means responsive to simultaneous occupancy of' the highway section and one of the'side sections to' prevent normal responsiveness of any initiating means that has not already responded from energizing the signal. i r 1 5. In a highway crossing system for railways foruse where a highway crosses a railway track, an approach track section wholly to" each side of the highway, a center-track section including the highway, a warning signal, means for ener-' gizingthe signal on occupancy of one approach section, and means effective upon'occupancy of the center section, for preventing occupancy of the other approach section from energizing the signal until after the said other approach section has been occupied and then vacated.

6. In a highway crossing system for railways, for use where a highway crosses a railway track. an approach track section wholly to each side of the highway, a center track section including the highway, a warning signal, means for energizing the signal on occupancy of one approach section, and means effective only upon occupancy of the center section, for preventing occupancy of the other approach section from energizing the signal until after the other approach section has been occupied and then vacated.

-lli 7.In a highway crossing system for railways, for use where a" highway crosses the railway track, an approach track section wholly to each side of the highway, a centertrack section including the highway, a warning signal, means for. energizing the signal on occupancy of one approach section, and means effective upon simultaneous occupancy of the center section and the .said one approach section, for preventing occupancy of the other approach section from energizing the signal until after the other approach section has been occupied and then vacated. I

8. In a signal system, a stretch of single track, a highway crossing the track,.means dividing the track into insulated sections, a center section wholly including. the. highway, and an approach section at each side of the highway, a warning signal, a track relay for each section, a control circuit for the signal including, in multiple, back points of the approach section relays, and a latching relay, effective to prevent release of the approach section relays if de-energized before de-energization of the approach section relays.

9...In a signal system, a stretch of single track, a highway crossing the track, means dividing the track into insulated sections including a center section wholly including the highway, and .an approach section at each side of the highway, a warning signal, a track relay for each block, a control circuit for the signal including in multiple, back points of the approach section relays, and a latching relay, controlled through a front point of the center section relay, effective to prevent release of the approach relays if de-energized before de-energization of the approach relays. V

10. In a signal system, a stretch of single track, a highway crossing the track, means dividing the track into insulated sections including, a center section wholly including the highway, and an approach section at each side of the highway,,a warning signal, a track relay for each block, a control circuit for the signal including inmultiple, back points of the approach section relays, and a latching relay controlled through a front point of the center section relay, and through a separate circuit including front points in series of the approach section relays, which latching relay is efiective to prevent release of the approach relays if de-energized before deenergization of the approach relays.

11. In a railway highway crossing signal system, in combination with a highway crossing a stretch of single track, and a signal, an isolated track section at each'side of the crossing, and an isolated track section including the highway, signal energizing means for each side section normally responsive to occupancy of its section to energize the signal, and lock means responsive to occupancy of the highway section to prevent any said signal energizing means, that has not already responded to energize the signal, from energizing the signal.

12. In a railway highway crossing signal system, in combination with a highway crossing a stretch of single track, and a signal, an isolated track section at each side of the crossing, and an isolated track section including the highway, signal energizing means for each side section normally responsive to occupancy of its section to energize the signal, and lock means responsive to, and not responsive unless, there be substantially simultaneous occupancy of the highway section and one of the side sections to prevent any said signal energizing means, that has not already responded to energize the signal, from energizing the signal.

13. In a railway highway crossing signal system, in combination with a highway crossing a stretch of single track, and a signal, an isolated track section at each side of the crossing, and an isolated track section including the highway, signal initiating means for each side section normally responsive to occupancy of its section to energize the signal, and lock means responsive only to the substantially simultaneous occupancy of the highway section and at least one other section, to prevent the said normal response of any said initiating means that has not already responded from energizing the signal.

14. In a highway crossing system for railways, for use where a highway crosses a railway track, an approach track section wholly to each side of the highway, a center track section including the highway, a warning signal, means for energizing the signal on occupancy of one approach section, and means effective upon the substantially simultaneous occupancy of the center section and said one approach section, for preventing occupancy of the other approach section from energizing the signal until after the said other approach section has been occu pied and then vacated.

15. In a highway crossing system for railways, for use where a highway crosses a railway track, an approach track section wholly to each side of the highway, a center track section including the highway, a warning signal, means for energizing the signal on occupancy of one approach section, and means effective only upon the substantially simultaneous occupancy of the center section and said one approach section, for preventing occupancy of the other approach section from energizing the signal until after the said otherapproach section has been occupied and then vacated.

WILLIAM S. HENRY. STUART J. MACKEY. 

